1. Field of the Invention
The present invention relates to a method for displaying a tool locus defined by NC data, and in particular to an improved method for displaying a tool locus defined by NC data for machining a surface having any shape, as successive dots aligned at a minute interval.
The present invention also relates to an improved method for displaying a tool locus defined by NC data for machining along minute segments defined in an XYZ-axial system, as a collection of minute segments or end points attached thereto.
The present invention further relates to an improved method for displaying based on data defined in five-axial system which additionally comprises A and B rotary axes.
2. Description of the Related Art
For machining a surface having a complicated shape, including die machining, NC-controlled machining is employed in a wide range of machining applications. For example, by using NC data prepared in CAD/CAM, any machining device, such as a machining center, capable of high speed feeding can achieve highly accurate and efficient machining for the complexity. In general, shape data for a machining object prepared by CAD or the like is converted into desired NC data in a CAM system. The NC data may comprise, for example, tool locus data and control data. Tool locus data is defined using XYZ axes. Control data may include a tool number, a feeding speed, a main spindle rotation speed, and so forth. Tool locus and control data are both supplied to machining devices such as a machining center.
Any defects caused on a surface which is machined based on NC data may be attributed to either the machining device or NC data in use. Specifically, NC data may be affected by errors in the CAD data or due to capacity tolerance due to a limited calculation speed, memory size, or the like, of a computer system used in CAM processing. Such a defect may often be as small as a few μm, or even smaller. When a machining device causes the defects, Locations of the defects can be predicted.
Whenever a defect is found, NC data is immediately analyzed. However, because very fine and precise machining often necessitate millions of dots to constitute dot data defining a tool locus, evaluation of the coordinate value of every dot is impossible.
Here, a CAM system is capable of displaying a created tool locus so that whether or not a desired shape is embodied as originally intended or the machining surface is free from any interference but with a tool can be confirmed. Although the image of a tool locus can be presented in an enlarged size, the magnification power is generally 1:1 for vertical:horizontal directions. This is not sufficient for an operator viewing the image on the monitor screen to find any disturbance of, for example, approx. 0.001 mm in the dot alignment with an interval of, for example, 1 mm or greater.
FIG. 1 shows several tool loci 101 for machining a curved surface 100 of a product W, and FIG. 2 shows an enlarged image of the portion B in FIG. 1. It is almost impossible, by only looking at the enlarged image B, to tell that these dots are not necessarily in smooth succession.
With the above as background, there has existed a strong demand for the ability to instantly understand, without delay, the location of any potential machining device-attributable defects and/or irregularity in shape of one or more tool locus/loci defined by NC data.